Illinois State Police on Friday agreed to review the Chicago Police Department’s investigation of the April 2004 homicide of David Koschman, who died after he was punched in the face by Richard “R.J.” Vanecko, a nephew of Mayor Richard Daley and White House Chief of Staff William Daley.

The state police investigation was requested Thursday by Cook County State’s Attorney Anita Alvarez, who said she wanted an outside, independent police agency to probe Koschman’s death in light of witnesses claiming that Chicago police inaccurately portrayed Koschman as the aggressor.

Alvarez said her office couldn’t examine the police inquiry because her staff has been involved in the case, determining there wasn’t enough evidence to file charges against Vanecko.